KR20240059656A - Materials, systems, and methods for foil encapsulation of airgels and airgel composites - Google Patents

Abstract

This disclosure relates to materials and systems for managing thermal runaway issues in energy storage systems. Exemplary embodiments include an insulating layer encapsulated to form an insulating barrier. The encapsulation layer is made of a laminate membrane comprising a malleable layer sandwiched between an outer and an inner polymer layer.

Description

Materials, systems, and methods for foil encapsulation of airgels and airgel composites

Cross-reference to related applications

This application is related to U.S. Provisional Patent Application No. 63/304,258, entitled “Materials, Systems, and Methods for Foil Encapsulation of Aerogels and Aerogel Composites,” filed on January 28, 2022, and “Materials, Systems, and Methods for Claims the benefit and priority of U.S. Provisional Patent Application No. 63/313,063, entitled “Foil Encapsulation of Aerogels and Aerogel Composites,” filed February 23, 2022. The contents of both provisional applications are incorporated herein by reference in their entirety.

Technology field

This disclosure generally relates to materials, systems, and methods for encapsulating materials. In particular, the present disclosure relates to materials, systems, and methods for encapsulation of thermal barriers used between battery cells or battery modules in energy storage systems. This disclosure relates to encapsulation of airgel thermal barriers. The present disclosure also relates to battery modules or packs having one or more battery cells comprising an encapsulated thermal barrier material, as well as systems containing such battery modules or packs.

Secondary batteries, such as lithium-ion batteries, are finding many uses in power drives and energy storage systems. Lithium-ion batteries (LIBs) are used to power other high-current devices such as cell phones, tablets, laptops, power tools, and electric vehicles due to their high operating voltage, low memory effect, and high energy density compared to traditional batteries. Widely used. However, LIBs are a safety concern because they are susceptible to catastrophic failure under “conditions of abuse,” such as when rechargeable batteries are overcharged (charged beyond designed voltage), overdischarged, or operated at or exposed to high temperatures and pressures. . As a result, narrow operating temperature ranges and charge/discharge rates are a limitation on the use of LIBs, as they may fail through rapid self-heating or thermal runaway events when they experience conditions outside their design window. Because you can.

Thermal runaway can occur when the internal reaction rate increases to the point where more heat is generated than can be withdrawn, resulting in a further increase in both the reaction rate and heat generation. During thermal runaway, high temperatures trigger a chain of exothermic reactions in the cell, causing the cell's temperature to rapidly increase. In many cases, when thermal runaway occurs in one battery cell, the heat generated is close to the cell experiencing thermal runaway and rapidly heats the cells. Each cell added to the thermal runaway reaction contains additional energy to continue the reaction, causing thermal runaway to propagate within the battery pack, ultimately resulting in disaster due to fire or explosion. Rapid heat dissipation and effective blocking of heat transfer paths can be effective measures to reduce the risk posed by thermal runaway propagation.

Based on the understanding of the mechanisms that lead to cell thermal runaway, many approaches are being studied with the goal of reducing safety risks through rational design of cell components. To prevent these successive thermal runaway events from occurring, LIBs typically employ sufficient insulating material between cells within a cell module or pack to keep the stored energy low enough, or to keep the cells from encountering adjacent cells. Designed to insulate against thermal events, or a combination of these. Electronics severely limits the amount of energy that can potentially be stored in these devices. The latter limits how close cells can be placed, thereby limiting the effective energy density.

Currently, there are a number of different methodologies employed to maximize energy density while protecting against subsequent thermal runaway. One approach is to incorporate a sufficient amount of insulation between the cells or clusters of cells. This approach is generally considered desirable from a safety perspective, but in this approach the ability of the insulating material to retain heat determines the upper limit of the energy density that can be achieved in combination with the required insulating volume.

Another approach is through the use of phase change materials. These materials undergo an endothermic phase change when a certain elevated temperature is reached. The endothermic phase change absorbs some of the heat generated, thereby cooling the localized area. Typically, for electrical storage devices, these phase change materials rely on hydrocarbon materials such as waxes and fatty acids, for example. Although these systems are effective for cooling, they are themselves flammable and therefore not beneficial in preventing thermal runaway if ignition occurs within the storage device.

Incorporation of intumescent materials is another strategy to prevent subsequent thermal runaway. These materials expand above a certain temperature, creating a char that is lightweight and designed to provide insulation when needed. Although these materials can be effective in providing thermal insulation benefits, their expansion must be considered in the design of the storage device.

Airgel materials have also been used as thermal barrier materials. Airgel thermal barriers offer many advantages over other thermal barrier materials. Some of these advantages include beneficial resistance to heat spread and fire spread while minimizing the thickness and weight of the materials used. Airgel thermal barriers also have advantageous properties for compressibility, compressibility, and compliance. Some airgel-based thermal barriers can be difficult to install between battery cells, especially in mass production environments, due to their light weight and low strength. Additionally, airgel thermal barriers tend to generate particulate matter (dust) that can be harmful to electrical storage systems, causing manufacturing problems.

With so many different materials available, each with many different properties, it would be desirable to encapsulate the thermal barrier material to provide additional protection for both the battery cells and the thermal barrier, while also simplifying the manufacturing process. It would be desirable.

The objective of the present disclosure is to eliminate or alleviate at least one disadvantage of the conventional methods and materials mentioned above. The support member provided herein is designed to improve encapsulation and handling of thermal barriers used in battery modules or battery packs.

In aspects of the present disclosure, a thermal insulating barrier for use in an electrical energy storage system includes at least one thermal insulating layer and an encapsulation layer at least partially surrounding the thermal insulating layer. The encapsulation layer includes a laminate membrane comprising an outer polymer layer, a malleable layer comprising a malleable material, and an inner polymer layer. The inner polymer layer is in contact with the insulating layer, and the malleable layer is disposed between the outer and inner polymer layers.

The outer polymer layer includes a polymer that resists the dielectric heat transfer fluid within the electrical energy storage system. For example, the outer polymer layer includes a polymer that resists heat transfer fluids selected from the group consisting of hydrocarbon fluids, ester fluids, silicone fluids, fluoroether fluids, and combinations thereof. In one aspect of the disclosure, the outer polymer layer is made of polyoxymethylene, acrylonitrile butadiene styrene, polyamide-imide, polyamide, polycarbonate, polyester, polyetherimide, polystyrene, polysulfone, polyimide, and tereptide. It is made from a polymer selected from the group consisting of phthalates.

The inner polymer layer comprises a polymer that can be heat welded to itself. For example, the inner polymer layer includes a polyolefin polymer. In some embodiments, the inner polymer is comprised of a different polymer than the polymer in the outer polymer layer.

The malleable layer, in some aspects, includes a metal foil. In some aspects, the malleable layer includes a malleable polymer.

In aspects of the present disclosure, the encapsulation layer further comprises an adhesive disposed between the outer polymer layer and the malleable layer and/or the inner polymer layer and the malleable layer.

In aspects of the present disclosure, the outer polymer layer has a thickness of about 10 μm to about 100 μm. In aspects of the present disclosure, the malleable layer has a thickness of about 10 μm to about 100 μm. In aspects of the present disclosure, the inner polymer layer has a thickness of about 10 μm to about 100 μm. In aspects of the present disclosure, the encapsulation layer has an overall thickness between about 30 μm and about 300 μm.

In aspects of the present disclosure, the insulating layer has a thermal conductivity through the thickness dimension of the insulating layer of less than about 50 mW/m-K at 25°C and less than about 60 mW/m-K at 600°C. In aspects of the present disclosure, the thermal insulating layer includes airgel.

In aspects of the present disclosure, the encapsulation layer completely surrounds the insulating layer. In an aspect of the present disclosure, the encapsulation layer is comprised of two laminate membranes heat welded together. In aspects of the present disclosure, the encapsulation layer surrounds the insulating layer. The encapsulation layer is heat welded to itself to form an enclosure that at least partially surrounds the insulating layer.

In an aspect of the present disclosure, a method of encapsulating an insulating layer for use between battery cells in an electrical energy storage system comprises: at least a portion of the insulating layer comprising an outer polymer layer, a malleable layer comprising a malleable material, and an inner polymer layer. Surrounding with a laminate membrane, wherein the inner polymer layer is in contact with the insulating layer and the malleable layer is disposed between the outer and inner polymer layers; and thermally welding the laminate membrane to form an encapsulation layer, the encapsulation layer at least partially surrounding the insulating layer.

In aspects of the present disclosure, a method of encapsulating a thermal insulation layer includes covering at least a portion of the thermal insulation layer with a first laminate film; covering at least a portion of the insulating layer with a second laminate film; and heat welding a portion of the first laminate membrane to the second laminate membrane to form the encapsulation layer.

In an aspect of the present disclosure, in a method of encapsulating an insulating layer, a first indentation is formed in the first laminate film, the first indentation being complementary in shape and size to the insulating layer; A second indentation is formed in the second laminate film, and the second indentation is complementary in shape and size to the insulating layer. Forming the encapsulation layer includes: disposing an insulating layer in the first indentation of the first laminate membrane; disposing the second laminate film on the first laminate film such that the second indentation is substantially aligned with the first indentation; and heat welding a portion of the first laminate membrane to a portion of the second laminate membrane.

In an aspect of the present disclosure, in a method of encapsulating an insulating layer, a first indentation is formed in the first laminate membrane, and the first indentation is complementary in shape and size to the insulating layer. A second indentation is formed in the second laminate film, the second indentation being complementary in shape and size to the first indentation. Forming the encapsulation layer includes: disposing an insulating layer in the first indentation of the first laminate membrane; disposing the second laminate film on the first laminate film with the second indentation substantially aligned with the first indentation such that a portion of the second indentation is disposed within the first indentation; and heat welding a portion of the first laminate membrane to a portion of the second laminate membrane.

In an aspect of the present disclosure, in a method of encapsulating an insulating layer, a first indentation is formed in the first laminate membrane, and the first indentation is complementary in shape and size to the insulating layer. A second indentation is formed in the second laminate film, the second indentation being complementary in shape and size to the first indentation. Forming the encapsulation layer includes: disposing an insulating layer in the first indentation of the first laminate membrane; disposing the second laminate film on the first laminate film with the second indentation substantially aligned with the first indentation such that a portion of the second indentation is disposed within the first indentation; and heat welding a portion of the first laminate membrane to a portion of the second laminate membrane.

In an aspect of the present disclosure, in a method of encapsulating an insulating layer, a first indentation is formed in the first laminate membrane, and the first indentation is complementary in shape and size to the insulating layer. A second indentation is formed in the laminate film, and the second indentation is complementary in shape and size to the insulating layer. At this point, forming the encapsulation layer includes: disposing an insulating layer in the first indentation of the laminate membrane; folding the laminate film so that the second indentation of the laminate film is substantially aligned with the first indentation; and heat welding a portion of the laminate membrane to itself.

In an aspect of the present disclosure, the thermally welded portions of the extending laminate membrane are folded against one or more sides of the insulating layer.

In another aspect of the present disclosure, a battery module includes a plurality of battery cells and one or more thermal insulating barriers as described herein disposed between adjacent battery cells.

In another aspect, a device or vehicle including a battery module or pack according to any of the above aspects is provided herein. In some embodiments, the device may include a laptop computer, a PDA, a mobile phone, a tag scanner, an audio device, a video device, a display panel, a video camera, a digital camera, a desktop computer, a military handheld computer, a military phone, a laser rangefinder, a digital communications device, an intelligent collection device, etc. Sensors, electronic integrated clothing, night vision equipment, power tools, calculators, radios, remote control devices, GPS devices, handheld and portable televisions, automobile starters, flashlights, acoustic devices, portable heating devices, portable vacuum cleaners or portable medical tools. . In some embodiments, the vehicle is an electric vehicle.

The thermal insulating barrier described herein may provide one or more advantages over existing thermal runaway mitigation strategies. The thermal insulating barrier described herein can minimize or eliminate cell thermal runaway propagation without significantly affecting the energy density and assembly cost of the battery module or pack. Thermal insulating barriers of the present disclosure can provide advantageous properties of compressibility, compression resilience, and compliance to accommodate continued swelling of the cell over the life of the cell while retaining advantageous thermal properties under normal operating conditions as well as thermal runaway conditions. The thermal insulating barriers described herein are durable and easy to handle, have advantageous resistance to heat propagation and fire propagation while minimizing the thickness and weight of the materials used, and also have advantageous properties of compressibility, compression resilience, and compliance. .

Accordingly, to describe the present disclosure in general terms, reference may be made to the accompanying drawings, which are not necessarily drawn to scale, in which: Figure 1a is a cross-sectional view of an insulating layer encapsulated by a laminate membrane;
Figure 1B is a side view of the laminate membrane.
Figure 1C is a side view of a laminate membrane with two outer polymer layers.
Figure 2A is a schematic diagram of the process of forming an encapsulation layer around an insulating layer using two laminate membrane sheets.
Figure 2b shows a schematic diagram of a thermal insulation layer encapsulated by an encapsulation layer formed by the process shown in Figure 2a.
Figure 2C shows a schematic diagram of an alternative process for forming an encapsulation layer around an insulating layer using a single laminate membrane sheet.
Figure 3A shows a schematic diagram of a process for forming an encapsulation layer around a thermal insulation layer using two laminate membrane sheets, where both sheets have indentations to receive the thermal insulation layer.
Figure 3b shows a top view of a thermal insulation layer encapsulated by an encapsulation layer formed by the process shown in Figure 3a.
Figure 3C shows a schematic diagram of an alternative process for forming an encapsulation layer around an insulating layer using a single laminate membrane sheet with two indentations.
Figure 4a shows a schematic diagram of an alternative process for forming an encapsulation layer around an insulating layer using two indented laminate membrane sheets.
Figure 4b shows a top view of a thermal insulation layer encapsulated by an encapsulation layer formed by the process shown in Figure 4a.
Figure 4C shows a schematic diagram of an alternative process for forming an encapsulation layer around an insulating layer using a single laminate membrane sheet with two indentations.
Figure 5A shows a schematic diagram of an alternative process for forming an encapsulation layer around an insulating layer using two laminate membrane sheets, one sheet indented but the other unindented.
Figure 5b shows a top view of a thermal insulation layer encapsulated by an encapsulation layer formed by the process shown in Figure 5a.
Figure 5C shows a schematic diagram of an alternative process for forming an encapsulation layer around an insulating layer using a single laminate membrane sheet with a single indentation in one section and no indentation in the other section.
Figure 6a shows a schematic diagram of a method of folding the encapsulation layer.
Figure 6b shows a schematic diagram of a method of folding an encapsulation with cutouts in the corners.
Figure 6c shows a schematic diagram of a method of double folding encapsulation layer edges.
Figure 7 shows a schematic diagram of an indentation formed in a laminate membrane.
Figure 8A shows a flow diagram of the assembly process for encapsulating a thermal insulating barrier with a single laminate membrane.
Figure 8b shows a flow diagram of the assembly process for encapsulating an insulating barrier with two laminate films.
Figure 9 shows a schematic diagram of a battery module with thermal insulating barriers between battery cells.
Although the invention is susceptible to various modifications and alternative forms, specific embodiments of the invention have been shown by way of example in the drawings and will be described in detail herein. Drawings may not be to scale. However, the drawings and the detailed description thereof are not intended to limit the invention to the specific form disclosed, but rather all modifications, equivalents, and alternatives that fall within the spirit and scope of the invention as defined by the appended claims. may include.

In the following detailed description of preferred embodiments, reference is made to the accompanying drawings, which form a part of the detailed description and illustrate by way of example specific embodiments in which the present disclosure may be practiced. It will be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present disclosure.

This disclosure relates to an insulating barrier and a system including insulating barriers to manage thermal runaway issues in an energy storage system. Exemplary embodiments include a thermally insulative barrier comprising at least one insulative layer and an encapsulation layer at least partially surrounding the insulative layer.

The insulating layer may include any type of insulating layer commonly used to separate battery cells or battery modules. Exemplary insulating layers include polymer-based thermal barriers (e.g., polypropylene, polyester, polyimide, and aromatic polyamide (aramid)), phase change materials, intumescent materials, airgel materials, mineral-based barriers (e.g., mica ), and inorganic thermal barriers (e.g., glass fiber containing barriers).

In a preferred embodiment, the thermal insulation layer comprises an airgel material. Descriptions of airgel insulation layers are described in U.S. Patent Application Publication No. 2021/0167438 and U.S. Provisional Patent Application No. 63/218,205, both of which are incorporated herein by reference.

The insulation layer has a temperature of about 50 mW/mK or less, about 40 mW/mK or less, about 30 mW/mK or less, about 25 mW/mK or less, about 20 mW/mK or less, about 18 mW at 25°C under a load of about 5 MPa or less. /mK or less, about 16 mW/mK or less, about 14 mW/mK or less, about 12 mW/mK or less, about 10 mW/mK or less, about 5 mW/mK or less, or a range between any two of these values. It may have thermal conductivity through the thickness index of the above-mentioned insulating layer.

Insulating layers can have a number of different physical properties that make it difficult to integrate the insulating layers into a battery module or battery pack. For example, some insulating layers have a very low flexural modulus (eg, less than 10 MPa), making the materials difficult to handle and position between battery cells. Additionally, low flexural modulus materials can be difficult to manipulate, especially when using automated encapsulation processes. Some insulation layers tend to generate particulate matter (dust) that can be harmful to electrical storage systems, causing manufacturing problems.

The present disclosure helps alleviate these problems by using an encapsulation layer that includes a laminate membrane. An encapsulation layer surrounds at least a portion of the insulating layer. In one embodiment, the laminate membrane includes an outer polymer layer, a malleable layer comprising a malleable material, and an inner polymer layer. The inner polymer layer is in contact with the insulating layer. The malleable layer is disposed between the outer and inner polymer layers. The inner and outer polymer layers act as a barrier to prevent damage to the thermal insulation layer from the surrounding atmosphere and fluids present in the energy storage system. The malleable layer also provides protection for the insulating layer, but the malleable layer also provides additional support to the insulating layer as a rigid but malleable support for the insulating layer.

An embodiment of a thermally insulating barrier comprising a thermally insulating layer encapsulated by an encapsulation layer is shown in Figure 1A. The heat insulating barrier 100 includes a heat insulating layer 110. Insulating layer 110 is surrounded by encapsulation layer 120. In an embodiment, the encapsulation layer is a laminate membrane comprising an outer polymer layer (122), a malleable layer (124), and an inner polymer layer (126). An enlarged side view of the laminate membrane is shown in Figure 1B. When used to encapsulate an insulating layer, inner polymer layer 126 is in contact with insulating layer 110. Malleable layer 124 is disposed between outer polymer layer 122 and inner polymer layer 126.

In some electrical energy storage systems, a fluid delivery system is coupled to the electrical energy storage system. During use, the fluid transfer system passes heat transfer fluid into the electrical energy storage system and collects the heat transfer fluid after the fluid passes through the electrical energy storage system. A fluid delivery system passes a dielectric liquid fluid or dielectric gas into an electrical energy storage system. In some aspects, the fluid is heated or cooled such that the fluid heats or cools components within the electrical energy storage system, respectively.

Exemplary dielectric heat transfer fluids include, but are not limited to, hydrocarbon fluids, ester fluids, silicone fluids, and fluoroether fluids. Hydrocarbon fluids that can be used to cool components of an electrical energy storage system include aromatic hydrocarbons (e.g., diethyl benzene and dibenzyl toluene) and aliphatic hydrocarbons (e.g., paraffin oil, isoparaffin oil, and polyalpha olefin), but is not limited thereto. Ester fluids that can be used to cool components of an electrical energy storage system include, but are not limited to, diester and polyolester heat transfer fluids. Silicone fluids that can be used to cool components of electrical energy storage systems include, but are not limited to, dimethylpolysiloxane, methylphenylpolysiloxane, diphenylpolysiloxane, and halogenated polysiloxane. Fluoroether fluids that can be used to cool components of electrical energy storage include, but are not limited to, perfluoropolyethers and hydrofluoroethers.

In one aspect of the disclosure, the outer polymer layer includes a polymer that resists the dielectric heat transfer fluid within the electrical energy storage system. In certain aspects of the present disclosure, the outer polymer layer includes a polymer that resists one or more heat transfer fluids commonly used in electrical energy storage systems. For example, the outer layer includes a polymer that resists hydrocarbon fluids, ester fluids, silicone fluids, fluoroether fluids, or any combination of these fluids. Exemplary polymers that can be used as the outer polymer layer include polyoxymethylene, acrylonitrile butadiene styrene, polyamide-imide, polyamide, polycarbonate, polyester, polyetherimide, polystyrene, polysulfone, polyimide, and terete. Including, but not limited to, phthalates, or combinations thereof.

The outer polymer layer can also provide wear protection to the thermal insulation layer. During use, external stresses can damage the insulation layer. Damage to the insulating layer can impair the insulating properties of the insulating layer. External stresses that may occur in an unprotected insulating layer include, but are not limited to, stress caused by expansion of battery cells, changes in ambient temperature, external shock, external rupture, and external scratching of the insulating layer. In some aspects of the present disclosure, the outer polymer layer is selected from materials that protect the insulating layer from external stresses. Exemplary polymers that can be used as the outer polymer layer include, but are not limited to, polyethylene terephthalate (“PET”) and oriented nylon (“ONy”).

Although a single outer polymer layer is described above, it should be understood that the outer polymer layer may be composed of two or more polymer layers. 1C shows an embodiment of the present disclosure with the outer layer consisting of two different polymer layers 122a and 122b. When multiple outer polymer layers are used, the additional outer polymer layers may be formed from the same polymer or different polymers. In an aspect of the invention, the outer polymer layer consists of an ONy polymer layer with an overlying PET polymer layer.

As shown in Figure 1A, inner polymer layer 126 contacts insulating layer 110. The inner polymer layer 110 at least partially surrounds the insulating layer and protects the insulating layer from external chemical and mechanical damage. The insulating layer also acts as a barrier to retain particulate material from the insulating layer contained within the encapsulation layer, inhibiting or preventing damaging particles from dispersing in the electrical energy storage system.

As discussed herein, encapsulation layer 120 is comprised of two separate laminate films (e.g., top film 120a and bottom film 120b) joined together to form a seal around insulating layer 110. ) can be composed of. In an alternative embodiment, the encapsulation layer may be formed from a single laminate membrane that is folded over and seals to itself to encapsulate the insulating layer.

In one aspect, the inner polymer layer 126 includes a material that can be heat welded to itself. As shown in Figure 1A, after encapsulating the insulating layer 110, the encapsulating layer 120 extends away from the insulating layer. For example, an inner polymer layer disposed on the top side of the insulation layer can be heat welded to an inner polymer layer disposed on the bottom side of the insulation layer to form a seal around the insulation layer. A heat seal may be formed by applying a heated object to the top laminate membrane and/or the bottom laminate membrane at a location outside the thermal insulation layer. The heat from the heated object will raise the temperature of the polymer to the point where the polymer used for the top and bottom layers can fuse together. Exemplary polymers that can be used as the inner layer of the laminate membrane are polyolefin polymers. Examples of polyolefin polymers that can be used as the inner polymer layer include, but are not limited to, polyethylene and polypropylene.

The inner polymer layer may also provide chemical and/or thermal resistance to the insulating layer. During use, the temperature of the battery cells may increase due to the electrical demands of the battery module. Likewise, battery modules may experience increased temperatures as electrical demands on the battery pack increase. An increase in the temperature of the components separated by the insulating layers can stress the insulating layer. Additionally, chemical leakage from the battery cells can chemically damage the insulating layer, compromising its thermal properties. In some aspects of the invention, the inner polymer layer is selected from materials that protect the insulating layer from chemical and thermal damage. Polyolefin polymers provide excellent chemical and thermal resistance to the insulation layer.

In one aspect, malleable layer 124 is disposed between inner polymer layer 126 and outer polymer layer 122. A malleable layer is used in some aspects to provide support and protection of the insulating barrier. For example, the insulating layer includes a woven or non-woven fibrous reinforcement support. Due to their light weight and low rigidity, these support-based insulation layers can be difficult to install within electrical energy storage systems, especially between battery cells. These difficulties are exacerbated in a mass production environment. Placing a malleable layer on the encapsulation layer can act as a support allowing the thermal insulating barrier to be more easily manipulated during manufacturing.

The malleable layer can also provide additional thermal and mechanical protection when used in battery modules. In some aspects of the present disclosure, a thermal insulating barrier is disposed between battery cells within a battery module. During a thermal runaway event, battery cells can explode explosively, releasing hot particles and gases throughout the module. This released material can cause adjacent battery cell casings to become damaged, sometimes causing adjacent battery cells to go into a runaway state. The thermal insulating barrier comprising a malleable layer can inhibit or prevent particulate matter and gases from damaging adjacent battery cells. The malleable layer can also protect the insulating layer from moisture and air.

In one aspect, the malleable layer comprises a malleable polymer or malleable metal foil. Aluminum is the most common metal used in laminate encapsulation layers, but other malleable metal foils such as stainless steel and copper foil can be used.

The use of metal foil can also add heat transfer properties to the insulating barrier. When thermal runaway of battery cells occurs, the battery cells are heated to very high temperatures. This heat can be radiated to adjacent battery cells, increasing the likelihood that adjacent battery cells will enter a runaway state. The use of metal foil can improve the thermal properties of the insulating barrier by providing a thermally conductive metal foil to the insulating layer. Heat generated by adjacent runaway battery cells can be transferred to the metal foil layer. The metal foil layer may be connected to a portion of the casing (eg, a cooling plate) that allows heat to be transferred away from the battery cells through the metal foil.

As discussed herein, the encapsulation layer is comprised of a laminate structure comprising an outer polymer layer, an inner polymer layer, and a malleable layer disposed between the polymer layers. In some aspects, the inner polymer layer is comprised of a different polymer material than the polymer of the outer polymer layer. For example, the inner polymer layer can be composed of a material that can be easily fused together, while the outer polymer layer can be composed of a material that resists coolant fluids used in electrical energy storage systems.

The laminate membrane used as the encapsulation layer may be constructed as a single membrane composed of multiple layers, as described herein. In an aspect, a laminate membrane may be formed by placing a malleable layer between two polymer layers and using heat and/or pressure to fuse the inner and outer polymer layers together. In other aspects, adhesive glue or tape may be used to hold the layers together. For example, the adhesive can be disposed between the outer polymer layer and the malleable layer and/or the inner polymer layer and the malleable layer.

In embodiments, the thickness of the encapsulation layer is from about 30 μm to about 300 μm. The encapsulation layer has a thickness of up to about 30 μm, up to about 40 μm, up to about 50 μm, up to about 60 μm, up to about 70 μm, up to about 80 μm, up to about 90 μm, up to about 100 μm, up to about 120 μm, up to about It may have a thickness of 150 μm, up to about 200 μm, up to about 250 μm, or up to about 300 μm. When the encapsulation layer is a laminate membrane, the inner polymer layer can have a thickness of about 10 μm to about 100 μm; The malleable layer may have a thickness of about 10 μm to about 100 μm; The outer polymer layer can have a thickness of about 10 μm to about 100 μm.

The insulating layer of the present disclosure, for example, an insulating layer comprising an airgel, can substantially maintain or increase thermal conductivity (typically measured in mW/m-k) under a load of about 5 MPa or less. In certain embodiments, the insulating layer of the present disclosure has a temperature of about 50 mW/mK or less, about 40 mW/mK or less, about 30 mW/mK or less, about 25 mW/mK or less, about 25°C under a load of about 5 MPa or less. 20 mW/mK or less, about 18 mW/mK or less, about 16 mW/mK or less, about 14 mW/mK or less, about 12 mW/mK or less, about 10 mW/mK or less, about 5 mW/mK or less, or these The thermal conductivity through the thickness index of the insulating layer is within a range between any two of the values. The thickness of the airgel insulation layer may be reduced as a result of the load on the airgel insulation layer. For example, the thickness of the airgel insulation layer is 50% or less, 40% or less, 30% or less, 25% or less, 20% or less, 15% or less, 10% or less, 5% or less, under a load of about 0.50 MPa to 5 MPa. Or it can be reduced by a range between any two of these values. As the thickness is reduced, the heat resistance of the insulating layer containing airgel may decrease, but the thermal conductivity may be maintained or increased by a substantial amount.

In one aspect, the encapsulation layer completely surrounds the insulating layer. Complete encapsulation of the insulating layer can be achieved by heat welding the two laminate membranes together. As used herein, the term “thermal welding” refers to the process of joining two pieces of polymeric materials by heat and fusing. In a thermal welding process, one or both of the polymer pieces are heated above the glass transition temperature of the material used to form one or both of the polymer pieces. Heating the polymer pieces above their glass transition temperature causes the material of one or both pieces to soften and fuse with the other piece.

In one aspect, a method of encapsulating an insulative layer includes: surrounding at least a portion of the insulative layer with a laminate membrane as described herein, and heat welding the laminate membrane to form an encapsulation layer, wherein the encapsulation layer at least partially encapsulates the insulative layer. Surrounded by - includes . Figure 2A shows one aspect of a method for encapsulating an insulating layer. In this embodiment, two separate laminate films 220a and 220b each cover at least a portion of the insulating layer 210. For example, the first laminate film 220a may cover the top surface of the insulation layer, and the second laminate film 220b may cover the bottom surface of the insulation layer. Both the first and second laminate films are positioned such that the inner polymer layers are in contact with each other. The encapsulation layer can be formed by heat welding a portion of the first laminate membrane to the second laminate membrane. For example, a heated element of the general shape of the insulating layer can be brought into contact with the first laminate film and pressed onto the first laminate film. The heated element causes the inner polymer layer of the first laminate membrane to fuse with the inner polymer layer of the second laminate membrane. Figure 2b shows a schematic diagram of a fully encapsulated thermal insulation layer.

In another aspect, the insulating layer is encapsulated by surrounding at least a portion of the insulating layer with a laminate membrane as described herein and heat welding the laminate membrane to form an encapsulation layer that at least partially surrounds the insulating layer. Figure 2C shows one aspect of a method for encapsulating an insulating layer. In this embodiment, the single laminate membrane 225 is folded upon itself such that each section of the single laminate membrane covers at least a portion of the insulating layer 210. For example, the first section 225a of the laminate film can cover the top surface of the insulation layer, and the second section 225b of the laminate film can cover the bottom surface of the insulation layer. Both the first and second sections of the laminate membranes are positioned such that the inner polymer layers are in contact with each other. The encapsulation layer can be formed by heat welding a portion of the first laminate membrane to the second laminate membrane. For example, a heated element of the general shape of the insulating layer can be brought into contact with the first laminate film and pressed onto the first laminate film. The heated element causes the inner polymer layer of the first laminate membrane to fuse with the inner polymer layer of the second laminate membrane.

As shown in FIG. 3A , the method of encapsulating the insulating layer 310 includes forming a first indentation 325 in a first laminate film 320 . The first indentation 325 is formed by bending the laminate film into a shape complementary in shape and size to the insulating layer. The presence of a malleable layer in the laminate membrane allows the first indentation to be formed and maintain the desired shape and size. A second indentation 335 is formed in the second laminate film 330. Both the first and second laminate films are arranged such that the insulating layer is located in the indentations. For example, in one aspect, insulating layer 310 is initially disposed in second indentation 335. The first laminate film 320 is then placed over the second laminate film such that the insulating layer is located in the first indentation 325. The encapsulation layer can be completed by heat welding a portion of the first laminate membrane to the second laminate membrane. Figure 3b shows a top view of a fully encapsulated insulating layer.

In an alternative embodiment, the encapsulation layer is self-sealing. In this alternative embodiment, the single encapsulation layer is long enough to fold upon itself and surround the insulating layer. Once folded, the encapsulation layer is heat welded to itself to encapsulate the insulating layer. Figure 3C shows a schematic diagram of a method of encapsulating the thermal insulation layer 310 with an encapsulation layer 350 comprising a single laminate membrane. A first indentation 354 and a second indentation 358 are formed in the laminate film 350. Both indentations have a size and shape complementary in size and shape to the insulating layer. In this embodiment, the encapsulation layer is formed by placing an insulating layer 310 in the first indentation 354. The laminate membrane is folded over itself such that the second indentation 358 is substantially aligned with the first indentation 354. The encapsulation layer can be completed by heat welding a portion of the first laminate membrane to the second laminate membrane.

An alternative method of encapsulating the insulating layer is shown in Figure 4a. In this alternative aspect, a method of encapsulating an insulating layer (410) includes forming a first indentation (425) in a first laminate film (420). The first indentation 425 is formed by bending the laminate film into a shape complementary in shape and size to the insulating layer. A second indentation 435 is formed in the second laminate film 430. The second indentation 435 has a shape and size that are complementary to the first indentation. Specifically, the second indentation 435 is shaped and sized to allow the indented portion of the second laminate film to fit into the first indentation. As shown in FIG. 4A , both the first and second laminate films are positioned such that the insulating layer is located within the first indentation 425 and on the second indentation 435 . For example, in one aspect, insulating layer 410 is initially disposed in first indentation 425 . The second laminate film 430 is then placed in contact with the first laminate film such that the insulating layer is positioned within the first indentation 425 and on the second indentation 435. The encapsulation layer can be completed by heat welding a portion of the first laminate membrane to the second laminate membrane. Figure 4b shows a top view of a fully encapsulated insulating layer.

In another aspect, a single laminate membrane is used to form the encapsulated insulating layer. Figure 4C shows an embodiment in which the single laminate film 450 is folded upon itself such that each section of the single laminate film covers at least a portion of the insulating layer 410. In an embodiment, a first indentation 465 is formed in the first section of the laminate membrane. The first indentation 465 is formed by bending the laminate film into a shape complementary in shape and size to the insulating layer. A second indentation 475 is formed in the second section of the laminate membrane. The second indentation 475 has a shape and size that are complementary to the first indentation. Specifically, the second indentation 475 is shaped and sized to allow the indented portion of the second laminate film to fit into the first indentation. As shown in Figure 4C, the first section of the laminate membrane and the second section of the laminate membrane are positioned such that the insulating layer is located within the first indentation 465 and on the second indentation 475. For example, in one aspect, insulating layer 410 is initially disposed in first indentation 465. A second section of laminate film 450 is folded over and placed in contact with the first laminate film such that the insulating layer is located within first indentation 465 and in contact with second indentation 475 . The encapsulation layer can be completed by heat welding a portion of the first section of the laminate membrane to a portion of a second section of the laminate membrane to form an encapsulated insulating layer.

An alternative method of encapsulating the insulating layer is shown in Figure 5a. As shown in FIG. 5A , a method of encapsulating an insulating layer 510 includes forming a first indentation 525 in a first laminate film 520 . The insulating layer 510 is located in the first indentation 525 . The second laminate film 530 is then placed in contact with the first laminate film such that the insulating layer is covered by the second laminate film. The encapsulation layer can be completed by heat welding a portion of the first laminate membrane to the second laminate membrane. Figure 5b shows a top view of a fully encapsulated insulating layer.

Figure 5C shows an embodiment in which a single laminate film 550 is folded upon itself such that each section of the single laminate film covers at least a portion of the insulating layer 510. As shown in Figure 5C, a first indentation 565 is formed in the first section of the laminate film 550. The insulating layer 510 is located in the first indentation 565. The first section 575 of the laminate membrane 550 is then placed in contact with the first section of the laminate membrane such that the insulating layer is covered by the second section of the laminate membrane. The encapsulation layer can be completed by heat welding a portion of the first section of the laminate membrane to a portion of the second section of the laminate membrane.

After the encapsulation layer has been formed, for example by heat welding the laminate film(s), there may be some additional material surrounding the insulating layer, typically portions of the encapsulation layer that are heat welded together. As shown in Figure 6A, the insulating layer is encapsulated by an encapsulation layer 620. A portion 625 of the heat-welded encapsulation layer extends away from the insulating layer. This can be a problem in some energy storage systems where there is very little additional space, if any, to accommodate these extended parts. In this aspect, the extended portions 625 can be folded back toward the insulating layer to reduce the size of the insulating barrier. In an alternative embodiment shown in FIG. 6B , cutouts 630 may be formed in the extended portion 625 . The cutouts allow the extended portion to be folded more easily, without creating bulging material at the corners, which could double the material if each edge of the encapsulation were folded toward the insulating layer. In some aspects, a double fold may be used.

Figure 6C shows an embodiment in which edges are folded twice. In Figure 6C, the insulating layer (not shown) is encapsulated by encapsulation layer 620. A portion 625 of the heat-welded encapsulation layer extends away from the insulating layer. The first fold is a 180 degree fold and the edge material is folded over itself. To also reduce the extended edges, the edge material is folded 90 degrees a second time so that the edge material is folded against the side of the pouch.

When indentations are used to form a pouch around an insulating barrier, the physical parameters of the indentation can be optimized to improve encapsulation of the insulating layer. Figure 7 shows a schematic diagram of an indentation 710 formed in a laminate film 700. Parameters of the indentation that can be changed to improve encapsulation of the insulating layer include depth (D); It includes the length (L), the angle of the indentation corner (θ _C ), and the radius of the edge (θ _E ). Factors can be optimized to take into account the malleable layer material and its thickness.

Figure 8a shows a general assembly process for encapsulation of a thermal insulation layer using a single laminate membrane. In a typical assembly process, both the laminate membrane and the insulation layer material are supplied as rolls that are fed into the assembly process. At start-up, both the laminate membrane and the insulation layer material are unrolled from the roll for processing. The laminate membrane is cut to the predetermined length required for encapsulation, and any indentations required for processing are formed in the laminate membrane. The insulating layer (in this example an airgel insulating layer) is also cut to the predetermined length required for use as a thermal barrier between battery cells or modules. Cutting materials are removed from the cutting machine and prepared for assembly. In this example, a single laminate sheet is used to encapsulate the insulation layer by folding the laminate sheet onto itself. The laminate membrane is prepared by forming fold lines or corrugations in the laminate membrane. An insulating layer (airgel) is then placed on the laminate membrane and appropriate portions of the membrane prepared for heat sealing. Both sides of the laminate membrane are heat welded together to partially surround the insulating layer, forming a bag-like enclosure with open ends. In some aspects, the open end of the bag is heat welded to complete the enclosure of the insulating layer. In an alternative embodiment, the partially encapsulated insulating layer is placed in a vacuum chamber. When the vacuum is drawn from the chamber, the open end of the encapsulation layer is sealed, completing the entire enclosure of the insulating layer under vacuum. The process is completed by selective lateral folding of the heat welded ends of the encapsulation layer.

Figure 8b shows a general assembly process for encapsulation of a thermal insulation layer using two laminate films. As discussed above, both the laminate membrane and the insulation layer material are supplied as rolls that are fed into the assembly process. At start-up, both the laminate membrane and the insulation layer material are unrolled from the roll for processing. The laminate membrane is cut into two separate pieces to the predetermined length required for encapsulation, and any indentations required for processing are formed in the laminate membrane. The insulating layer (in this example an airgel insulating layer) is also cut to the predetermined length required for use as a thermal barrier between battery cells or modules. Cutting materials are removed from the cutting machine and prepared for assembly. In this example, two laminate sheets are used to encapsulate the thermal insulation layer. An insulating layer (airgel) is placed on the laminate membrane and appropriate portions of the membrane prepared for heat sealing. Both sides and one end of the laminate membrane are heat welded together to partially surround the insulating layer, forming a bag-like enclosure with open ends. In some embodiments, the open end of the bag is simply heat welded to complete the enclosure of the insulating layer. In an alternative embodiment, the partially encapsulated insulating layer is placed in a vacuum chamber. When the vacuum is drawn from the chamber, the open end of the encapsulation layer is sealed, completing the entire enclosure of the insulating layer under vacuum. The process is completed by selective lateral folding of the heat welded ends of the encapsulation layer.

A test protocol was developed to determine the effectiveness of the thermal insulating barriers described herein. The test protocol tests the ability of the insulating barrier to resist high temperatures and the effects of heated particles. This mimics the rupture conditions that can occur during thermal runaway of a battery cell. In both tests, the thermal barrier is bonded to a metal support plate (eg, a stainless steel plate). A thermal sensor is attached to the support plate to monitor the temperature of the metal support plate during use.

To test the thermal resistance of an insulating barrier, the insulating barrier is bonded to a support plate and subjected to a flame test. A propane torch (benzomatic) is used to develop a temperature of approximately 1000° C. on the insulating barrier. The heat of the support plate can be monitored during testing to determine the thermal resistance of the insulation layer. After the flame test is completed, the insulation layer is observed for damage. In an exemplary flame test protocol, an insulating barrier is coupled to a support and a propane torch is used to heat the insulating layer at 1000° C. for 2 minutes. The insulation layer is then observed for damage.

The testing protocol also includes heated particle testing. In heated particle testing, the same flame test system is used but modified to include heated particles. In an exemplary experiment, an insulating barrier mounted on a support is heated to approximately 1000°C. A stream of particles inert at operating temperature (about 1000° C.) was directed to the insulating barrier in such a way that the particles were heated by a torch before hitting the insulating barrier. The heated particles were directed towards the insulating barrier for 10 seconds. After the heated particles had stopped, the insulating barrier was heated at 1000°C for 2 min without particles.

In both tests, the insulating barrier maintained its integrity and insulating properties. The polymer layers burned under the test conditions, but the malleable layer (stainless steel) and the insulating layer (airgel) only discolored. The encapsulating member can reduce or eliminate the production of dust or particulate material shed from the insulating layer. Additionally, the encapsulation layer may be formed of a material that allows markings or printed records to be made on the insulating barrier. Marking of the insulation layer is not always possible.

As used in this specification and the appended claims, the singular forms include plural referents unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term “or” is generally employed to include “and/or” unless the context clearly dictates otherwise.

As used herein, “about” means approximately or approximately, and in situations where a numerical value or range is presented, it means ±5% of the numerical value. In embodiments, the term “about” may include traditional rounding to significant figures of a numerical value. Additionally, the phrase “about ‘x’ to ‘y’” includes “about ‘x” to about ‘y’”.

Within the context of this disclosure, the terms “airgel”, “airgel material” or “airgel matrix” include a framework of interconnected structures, with a corresponding network of interconnected pores incorporated within the framework, and a dispersed interstitial medium. refers to a gel containing a gas such as air; It is characterized by the following physical and structural properties (according to nitrogen porosimetry tests) attributed to the airgel: (a) an average pore diameter ranging from about 2 nm to about 100 nm, (b) a porosity of at least 80% or more, and (c) Surface area greater than about 100 m ² /g by nitrogen sorption analysis.

Accordingly, the airgel material of the present disclosure is any airgel or other open cell that satisfies the defining elements set forth in the previous paragraphs, including materials that may be otherwise classified as xerogel, kriegel, ambigel, microporous material, etc. Includes ingredients.

Within the context of this disclosure, reference to “thermal runaway” generally refers to a sudden rapid increase in cell temperature and pressure due to various operating factors, which may in turn result in the propagation of excessive temperatures throughout the associated module. . Potential causes of thermal runaway in these systems include, for example, cell defects and/or short circuits (both internal and external), overcharging, cell puncture or rupture, such as in case of an accident, and excessive ambient temperatures, e.g. , typically greater than 55°C). In normal use, the cell heats up as a result of internal resistance. Under normal power/current loading and ambient operating conditions, the temperature within most Li-ion cells can be relatively easily controlled to be maintained within the range of 20°C to 55°C. However, faulty individual cells as well as stressful conditions such as high power draw at high cell/ambient temperatures can cause localized heating to increase steeply. In particular, above the critical temperature, exothermic chemical reactions within the cell are activated. Moreover, chemical exotherm typically increases exponentially with temperature. As a result, heat generation becomes much greater than the available heat dissipation. Thermal runaway can lead to internal temperatures exceeding 200°C and cell venting.

Within the context of this disclosure, the terms “flexible” and “flexibility” mean the ability of a material or composition to bend or flex without macrostructural failure. The insulating layer of the present disclosure can bend at least 5°, at least 25°, at least 45°, at least 65°, or at least 85° without macroscopic fracture and/or bends less than 4 feet, less than 2 feet, less than 1 foot without macroscopic fracture. It has a bend radius of less than, less than 6 inches, less than 3 inches, less than 2 inches, less than 1 inch, or less than U inch. Likewise, the terms “highly flexible” or “highly flexible” refer to a material that can be bent at least 90° without macroscopic failure and/or has a bend radius of less than U inches. Additionally, the terms “classified as flexible” and “classified as flexible” refer to a material or composition that can be classified as flexible according to ASTM C1 101 (ASTM International, West Conshohocken, PA).

The insulating layer of the present disclosure can be classified as flexible, highly flexible, and/or flexible. Airgel compositions of the present disclosure may also be drapable. Within the context of this disclosure, the terms “drapable” and “drapeability” refer to the ability of a material to bend or bend more than 90° with a radius of curvature of about 4 inches or less without macroscopic failure. The insulating layer according to certain embodiments of the present disclosure may be flexible so that the composition is non-rigid and can be applied and conformed to a three-dimensional surface or object, or may be preformed into various shapes and configurations to simplify installation or application. .

Within the context of this disclosure, the terms “thermal conductivity” and “TC” refer to the temperature difference between two surfaces on either side of a material or composition and a measure of the ability of a material or composition to transfer heat between the two surfaces. refers to Specifically, thermal conductivity is measured as the heat energy transferred per unit time and per unit surface area divided by the temperature difference. Typically written in SI units as mW/m*K (milliwatts per meter * Kelvin). The thermal conductivity of the material was measured using the Test Method for Steady-State Thermal Transmission Properties by Means of the Heat Flow Meter Apparatus (ASTM C518, ASTM International, West Conshohocken, PA); Test Method for Steady-State Heat Flux Measurements and Thermal Transmission Properties by Means of the Guarded-Hot-Plate Apparatus (ASTM C177, ASTM International, West Conshohocken, PA); Test Method for Steady-State Heat Transfer Properties of Pipe Insulation (ASTM C335, ASTM International, West Conshohocken, PA); Thin Heater Thermal Conductivity Test (ASTM C1114, ASTM International, West Conshohocken, PA); Standard Test Method for Thermal Transmission Properties of Thermally Conductive Electrical Insulation Materials (ASTM D5470, ASTM International, West Conshohocken, PA); Determination of thermal resistance by means of guarded hot plate and heat flow meter methods (EN 12667, British Standards Institution, United Kingdom); or Determination of steady-state thermal resistance and related properties - can be determined by test methods known in the art, including but not limited to Guarded hot plate apparatus (ISO 8203, International Organization for Standardization, Switzerland). Due to different methods that can lead to different results, within the context of this disclosure, unless explicitly stated otherwise, thermal conductivity measurements are referred to in the ASTM C518 standard (Test Method for Steady-State Thermal Transmission Properties by Means of the Heat). According to the Flow Meter Apparatus), it should be understood that the test was conducted under a compressive load of approximately 2 psi and a temperature of approximately 37.5°C at atmospheric pressure in an ambient environment. Measurements recorded according to ASTM C518 typically correlate well with any measurements made according to EN 12667 with any relevant adjustment for compressive load.

Thermal conductivity measurements can also be made under compression and at a temperature of about 10°C at atmospheric pressure. Thermal conductivity measurements at 10°C are typically 0.5 to 0.7 mW/mK lower than the corresponding thermal conductivity measurements at 37.5°C. In certain embodiments, the insulating layer of the present disclosure has a temperature of about 40 mW/mK or less, about 30 mW/mK or less, about 25 mW/mK or less, about 20 mW/mK or less, about 18 mW/mK or less, about Has a thermal conductivity within a range of 16 mW/mK or less, about 14 mW/mK or less, about 12 mW/mK or less, about 10 mW/mK or less, about 5 mW/mK or less, or between any two of these values. .

Use of thermal insulation barriers within cell modules or packs

Lithium-ion batteries (LIBs) are considered one of the most important energy storage technologies due to their high operating voltage, low memory effect, and high energy density compared to traditional batteries. However, safety concerns are a significant obstacle preventing large-scale application of LIB. Under abusive conditions, exothermic reactions can result in heat release that can cause subsequent unsafe reactions. If this situation worsens, the heat released from the abused cell can activate the reaction chain, resulting in catastrophic thermal runaway.

With continuous improvements in the energy density of LIBs, improving safety for the development of electrical devices, such as electric vehicles, is becoming increasingly urgent. The mechanisms underlying safety issues vary depending on the cell chemistry. The present technology focuses on tailoring thermal insulating barriers and corresponding configurations of these tailored barriers to obtain advantageous thermal and mechanical properties. The insulating barrier of the present technology ensures the stability of the LIB under normal operating modes (e.g., withstanding applied compressive stress), while providing an effective heat dissipation strategy under normal as well as thermal runaway conditions.

Thermal insulating barriers disclosed herein can be used to package battery cells or battery components of any configuration, such as pouch cells, cylindrical cells, prismatic cells, as well as packs and modules incorporating or containing any such cells. Useful for separating, insulating and protecting. The batteries disclosed herein are useful in secondary batteries, such as lithium ion batteries, solid state batteries, and other energy storage devices or technologies that require separation, insulation, and protection.

Passive devices, such as cooling systems, can be used with the thermal insulating barriers of the present disclosure within a battery module or battery pack.

The thermal insulation barrier according to various embodiments of the present disclosure in a battery pack includes a plurality of single battery cells or modules of battery cells to thermally isolate the plurality of single battery cells or modules of battery cells from each other. A battery module consists of multiple battery cells arranged in a single enclosure. A battery pack consists of multiple battery modules. 9 shows an embodiment of a battery module 900 having a plurality of battery cells 950. Encapsulated thermal insulating barriers 925 are positioned between the battery cells 950. The encapsulated thermal barrier can inhibit or prevent damage to adjacent battery cells when a battery cell experiences thermal runaway or any other catastrophic battery cell failure.

Battery modules and battery packs can be used to supply electrical energy to devices or vehicles. Devices that use battery modules or battery packs include laptop computers, PDAs, mobile phones, tag scanners, audio devices, video devices, display panels, video cameras, digital cameras, desktop computers, military portable computers, military phones, laser range finders, and digital communication devices. , intelligent collection sensors, electronic integrated clothing, night vision equipment, power tools, calculators, radios, remote control devices, GPS devices, handheld and portable televisions, car starters, flashlights, acoustic devices, portable heating devices, portable vacuum cleaners or portable Including, but not limited to, medical instruments. When used in a vehicle, the battery pack can be used in any electric vehicle or hybrid vehicle.

Aspects of the disclosure are presented in the following numbered provisions:

Article 1. A thermal insulating barrier for use in electrical energy storage systems, comprising:

at least one insulating layer; and

an encapsulating layer at least partially surrounding the insulating layer, the encapsulating layer comprising an outer polymeric layer, a malleable layer comprising a malleable material, and an inner polymeric layer, the inner polymeric layer being in contact with the insulating layer, and the malleable layer being adjacent to the outer polymeric layer and the inner polymeric layer. Disposed between polymer layers - A semiconductor device comprising:

Clause 2. The thermal insulating barrier of clause 1, wherein the outer polymer layer comprises a polymer that resists a dielectric heat transfer fluid in the electrical energy storage system.

Clause 3. The method of clause 2, wherein the outer polymer layer comprises a polymer that resists heat transfer fluids selected from the group consisting of hydrocarbon fluids, ester fluids, silicone fluids, fluoroether fluids, and mixtures thereof. Insulating barrier.

Clause 4. The method of any one of clauses 1 to 3, wherein the outer polymer layer is made of polyoxymethylene, acrylonitrile butadiene styrene, polyamide-imide, polyamide, polycarbonate, polyester, polyetherimide, A thermal insulating barrier made from a polymer selected from the group consisting of polystyrene, polysulfone, polyimide, and terephthalate.

Clause 5. The thermal insulating barrier according to any one of clauses 1 to 4, wherein the inner polymer layer consists of a polymer that can be heat welded to itself.

Clause 6. The thermal insulating barrier according to any one of clauses 1 to 5, wherein the inner polymer layer consists of a polyolefin polymer.

Clause 7. The thermal insulating barrier of any one of clauses 1 to 6, wherein the inner polymer layer is comprised of a different polymer than the polymer in the outer polymer layer.

Clause 8. The method of any one of clauses 1 through 7, wherein the outer polymer layer is comprised of polyethylene terephthalate (“PET”) or oriented nylon (“ONy”) and the inner polymer layer is comprised of polypropylene (“ONy”). A thermal insulating barrier consisting of PP").

Clause 9. The method of any one of clauses 1 to 8, wherein the outer polymer layer is comprised of a first polymer membrane comprised of a first material and a second polymer membrane comprised of a second material, wherein the first material is comprised of a second polymer membrane. Thermal insulating barriers, which are different materials.

Clause 10. The thermal insulating barrier of any one of clauses 1 to 9, wherein the malleable layer comprises a metal foil.

Clause 11. The thermal insulating barrier of any one of clauses 1-10, wherein the malleable layer comprises a malleable polymer.

Clause 12. The thermal insulating barrier according to any one of clauses 1 to 11, wherein the encapsulating layer further comprises an adhesive disposed between the outer polymer layer and the malleable layer and/or the inner polymer layer and the malleable layer.

Clause 13. The thermal insulating barrier of any one of clauses 1-12, wherein the outer polymer layer has a thickness of from about 10 μm to about 100 μm.

Clause 14. The thermal insulating barrier of any one of clauses 1-13, wherein the malleable layer has a thickness of about 10 μm to about 100 μm.

Clause 15. The thermal insulating barrier of any one of clauses 1 to 14, wherein the inner polymer layer has a thickness of from about 10 μm to about 100 μm.

Clause 16. The thermal insulating barrier of any one of clauses 1 to 15, wherein the encapsulation layer has an overall thickness of between about 30 μm and about 300 μm.

Clause 17. The method of any one of clauses 1 to 16, wherein the insulating layer has a thermal conductivity through the thickness dimension of the insulating layer of less than about 50 mW/m-K at 25°C and less than about 60 mW/m-K at 600°C. Phosphorus, thermal insulating barrier.

Clause 18. The thermal insulating barrier of any one of clauses 1 to 17, wherein the thermal insulating layer comprises airgel.

Clause 19. The thermal insulating barrier according to any one of clauses 1 to 18, wherein the encapsulating layer completely surrounds the thermal insulating layer.

Clause 20. The thermal insulating barrier according to any one of clauses 1 to 19, wherein the encapsulation layer consists of two laminate membranes welded together.

Clause 21. The thermal insulating barrier according to any one of clauses 1 to 20, wherein the encapsulating layer surrounds the thermal insulating layer, and the encapsulating layer is heat welded to itself to form an enclosure that at least partially surrounds the thermal insulating layer. .

Clause 22. A battery module, comprising:

a plurality of battery cells, and

A battery module comprising one or more thermal insulation barriers according to any one of clauses 1 to 21, wherein at least one thermal insulation barrier is disposed between adjacent battery cells.

Article 23. A power system comprising one or more battery modules as described in Article 22.

Article 24. Device or vehicle comprising a power system according to Article 23.

Clause 25. The provisions of Clause 24, wherein devices include laptop computers, PDAs, mobile phones, tag scanners, audio devices, video devices, display panels, video cameras, digital cameras, desktop computers, military portable computers, military telephones, laser rangefinders, and digital communication devices. , intelligent collection sensors, electronic integrated clothing, suggestive equipment, power tools, calculators, radios, remote control devices, GPS devices, handheld and portable televisions, car starters, flashlights, acoustic devices, portable heating devices, portable vacuum cleaners or portable A device that is a medical tool.

Clause 26. The vehicle of Clause 24, wherein the vehicle is an electric vehicle.

Clause 27. A method of encapsulating an insulating layer for use between battery cells in an electrical energy storage system, comprising:

Surrounding at least a portion of the insulating layer with a laminate membrane comprising an outer polymeric layer, a malleable layer comprising a malleable material, and an inner polymeric layer, wherein the inner polymeric layer is in contact with the thermal insulating layer, and the malleable layer is in contact with the outer polymeric layer and the inner polymeric layer. placed between floors -; and

Heat welding the laminate membrane to form an encapsulation layer, the encapsulation layer at least partially surrounding the thermal insulation layer.

Clause 28. The method of clause 27, wherein forming the encapsulation layer comprises:

covering at least a portion of the thermal insulation layer with a first laminate film;

covering at least a portion of the insulation layer with a second laminate film; and

The method comprising heat welding a portion of the first laminate membrane to a second laminate membrane to form an encapsulation layer.

Article 29. In Article 28:

A first indentation is formed in the first laminate film, the first indentation being complementary in shape and size to the insulating layer;

a second indentation is formed in the second laminate film, the second indentation being complementary in shape and size to the insulating layer; and

The steps for forming the encapsulation layer are:

disposing an insulating layer in the first indentation of the first laminate membrane;

disposing the second laminate film on the first laminate film such that the second indentation is substantially aligned with the first indentation; and

The method comprising heat welding a portion of the first laminate membrane to a portion of the second laminate membrane.

Article 30. In Article 28:

A first indentation is formed in the first laminate film, the first indentation being complementary in shape and size to the insulating layer;

a second indentation is formed in the second laminate film, the second indentation being complementary in shape and size to the first indentation; and

The steps for forming the encapsulation layer are:

disposing an insulating layer in the first indentation of the first laminate membrane;

disposing the second laminate film on the first laminate film with the second indentation substantially aligned with the first indentation such that a portion of the second indentation is disposed within the first indentation; and

The method comprising heat welding a portion of the first laminate membrane to a portion of the second laminate membrane.

Article 31. In Article 28:

A first indentation is formed in the first laminate film, the first indentation being complementary in shape and size to the insulating layer;

The steps for forming the encapsulation layer are:

disposing an insulating layer in the first indentation of the first laminate membrane;

disposing a second laminate film over the first laminate film; and

The method comprising heat welding a portion of the first laminate membrane to a portion of the second laminate membrane.

Article 32. In Article 27:

A first indentation is formed in the laminate film, the first indentation being complementary in shape and size to the insulating layer;

A second indentation is formed in the laminate film, the second indentation being complementary in shape and size to the insulating layer; and

The steps for forming the encapsulation layer are:

disposing an insulating layer in the first indentation of the laminate membrane;

folding the laminate film so that the second indentation of the laminate film is substantially aligned with the first indentation; and

A method comprising heat welding a portion of the laminate membrane to itself.

Article 33. In Article 27:

A first indentation is formed in the laminate film, the first indentation being complementary in shape and size to the insulating layer; and

The steps for forming the encapsulation layer are:

disposing an insulating layer in the first indentation of the laminate membrane;

folding the laminate membrane so that a portion of the laminate membrane substantially covers the insulation layer and a separate portion of the laminate membrane; and

A method comprising heat welding a portion of the laminate membrane to itself.

Clause 34. The method of any one of clauses 27-33, wherein the encapsulating layer completely surrounds the insulating layer.

Clause 35. The method of any one of clauses 27 to 34, wherein the heat welded portions of the laminate membrane are folded against one or more sides of the thermal insulation layer.

Certain U.S. patents, U.S. patent applications, and other materials (e.g., papers) are incorporated by reference into this patent. However, the text of these U.S. patents, U.S. patent applications, and other materials is incorporated by reference only to the extent that no conflict exists between such text and other statements and drawings set forth herein. In the event of such a conflict, any such conflicting text incorporated by U.S. patents, U.S. patent applications, and other materials is not incorporated by reference into this patent.

Additional modifications and alternative embodiments of the various aspects of the invention will be apparent to those skilled in the art upon consideration of this description. Accordingly, this description should be construed as illustrative only, and is for the purpose of teaching those skilled in the art the general manner of carrying out the invention. It is to be understood that the forms of the invention shown and described herein are to be taken as examples of embodiments. Elements and materials may be substituted for those illustrated and described herein, parts and processes may be reversed, and certain features of the invention may be used independently, all of which may be used independently in the present description of the invention. It will be clear to those skilled in the art after obtaining the advantages of. Changes may be made in the elements described herein without departing from the spirit and scope of the invention as set forth in the following claims.

As used in the specification and claims, the terms “comprise” and “comprising” and their conjugations mean that specific features, steps or integers are included. Terms should not be construed to exclude the presence of other features, steps or components.

Although certain exemplary embodiments of the invention have been described, the scope of the appended claims is not intended to be limited to these embodiments only. The claims are to be construed literally, intentionally, and/or to encompass equivalents.

Claims (35)

A thermal insulating barrier for use in an electrical energy storage system, comprising:
at least one insulating layer; and
an encapsulating layer at least partially surrounding the insulating layer, the encapsulating layer comprising an outer polymeric layer, a malleable layer comprising a malleable material, and an inner polymeric layer, the inner polymeric layer being in contact with the insulating layer, the malleable layer comprising: Disposed between said outer polymer layer and said inner polymer layer. The thermal insulating barrier of claim 1, wherein the outer polymer layer comprises a polymer that resists dielectric heat transfer fluid within the electrical energy storage system. 3. The thermal insulating barrier of claim 2, wherein the outer polymer layer comprises a polymer that resists heat transfer fluids selected from the group consisting of hydrocarbon fluids, ester fluids, silicone fluids, fluoroether fluids, and mixtures thereof. . 4. The method of any one of claims 1 to 3, wherein the outer polymer layer is made of polyoxymethylene, acrylonitrile butadiene styrene, polyamide-imide, polyamide, polycarbonate, polyester, polyetherimide, polystyrene, A thermal insulating barrier made from a polymer selected from the group consisting of polysulfone, polyimide, and terephthalate. 5. Thermal insulating barrier according to claim 1, wherein the inner polymer layer consists of a polymer that can be heat welded to itself. 6. Thermal insulating barrier according to any one of claims 1 to 5, wherein the inner polymer layer consists of a polyolefin polymer. 7. Thermal insulating barrier according to any one of claims 1 to 6, wherein the inner polymer layer is composed of a different polymer than the polymer in the outer polymer layer. 8. The method of any one of claims 1 to 7, wherein the outer polymer layer is comprised of polyethylene terephthalate ("PET") or oriented nylon ("ONy") and the inner polymer layer is polypropylene ("PP"). "), an insulating barrier consisting of 9. The method of claim 1, wherein the outer polymer layer is comprised of a first polymer film made of a first material and a second polymer film made of a second material, wherein the first material is comprised of the second polymer film. Thermal insulating barriers, which are different materials. 10. Thermal insulating barrier according to any preceding claim, wherein the malleable layer comprises a metal foil. 11. The thermal insulating barrier according to any one of claims 1 to 10, wherein the malleable layer comprises a malleable polymer. 12. The thermal insulation according to any one of claims 1 to 11, wherein the encapsulation layer further comprises an adhesive disposed between the outer polymer layer and the malleable layer and/or the inner polymer layer and the malleable layer. Barrier. 13. The thermal insulating barrier of any preceding claim, wherein the outer polymer layer has a thickness of about 10 μm to about 100 μm. 14. The thermal insulating barrier of any preceding claim, wherein the malleable layer has a thickness of about 10 μm to about 100 μm. 15. The thermal insulating barrier of any one of claims 1 to 14, wherein the inner polymer layer has a thickness of about 10 μm to about 100 μm. 16. Thermal insulating barrier according to any one of claims 1 to 15, wherein the encapsulation layer has an overall thickness of between about 30 μm and about 300 μm. 17. The method of any one of claims 1 to 16, wherein the insulating layer has a thermal conductivity through the thickness dimension of the insulating layer of less than about 50 mW/m-K at 25°C and less than about 60 mW/m-K at 600°C. , thermal insulation barrier. 18. The thermal insulating barrier according to any one of claims 1 to 17, wherein the thermal insulating layer comprises airgel. 19. Thermal insulating barrier according to any one of claims 1 to 18, wherein the encapsulation layer completely surrounds the insulating layer. 20. Thermal insulating barrier according to any one of claims 1 to 19, wherein the encapsulation layer consists of two laminate membranes welded together. 21. The insulating layer according to any one of claims 1 to 20, wherein the encapsulating layer surrounds the insulating layer, and the encapsulating layer is heat welded to itself to form an enclosure that at least partially surrounds the insulating layer. Barrier. As a battery module,
a plurality of battery cells, and
A battery module comprising one or more thermal insulation barriers according to any one of claims 1 to 21, wherein at least one thermal insulation barrier is disposed between adjacent battery cells. A power system comprising one or more battery modules as described in claim 22. A device or vehicle comprising a power system according to claim 23. 25. The device of claim 24, wherein the device includes a laptop computer, a PDA, a mobile phone, a tag scanner, an audio device, a video device, a display panel, a video camera, a digital camera, a desktop computer, a military portable computer, a military phone, a laser rangefinder, a digital communication device, an intelligent Acquisition sensors, electronically integrated clothing, night vision equipment, power tools, calculators, radios, remote control devices, GPS devices, handheld and portable televisions, automobile starters, flashlights, acoustic devices, portable heating devices, portable vacuum cleaners, or portable medical tools. A device. 25. The vehicle of claim 24, wherein the vehicle is an electric vehicle. A method of encapsulating an insulating layer for use between battery cells in an electrical energy storage system, comprising:
Surrounding at least a portion of the insulating layer with a laminate membrane comprising an outer polymeric layer, a malleable layer comprising a malleable material, and an inner polymeric layer, wherein the inner polymeric layer is in contact with the insulating layer, and the malleable layer is adjacent to the outer polymeric layer. disposed between a polymer layer and said inner polymer layer; and
heat welding the laminate membrane to form an encapsulation layer, the encapsulation layer at least partially surrounding the insulating layer. 28. The method of claim 27, wherein forming the encapsulation layer comprises:
covering at least a portion of the insulating layer with a first laminate film;
covering at least a portion of the insulation layer with a second laminate film; and
heat welding a portion of the first laminate membrane to the second laminate membrane to form the encapsulation layer. According to clause 28,
A first indentation is formed in the first laminate film, and the first indentation is complementary in shape and size to the insulating layer;
a second indentation is formed in the second laminate film, and the second indentation is complementary in shape and size to the insulating layer; and
The steps of forming the encapsulation layer are:
disposing the insulating layer in a first indentation in the first laminate membrane;
disposing the second laminate film on the first laminate film such that the second indentation is substantially aligned with the first indentation; and
and heat welding a portion of the first laminate membrane to a portion of the second laminate membrane. According to clause 28,
A first indentation is formed in the first laminate film, and the first indentation is complementary in shape and size to the insulating layer;
a second indentation is formed in the second laminate film, the second indentation being complementary in shape and size to the first indentation; and
The steps of forming the encapsulation layer are:
disposing the insulating layer in a first indentation in the first laminate membrane;
disposing the second laminate film on the first laminate film with the second indentation substantially aligned with the first indentation such that a portion of the second indentation is disposed within the first indentation; and
and heat welding a portion of the first laminate membrane to a portion of the second laminate membrane. According to clause 28,
A first indentation is formed in the first laminate film, and the first indentation is complementary in shape and size to the insulating layer;
The steps of forming the encapsulation layer are:
disposing the insulating layer in a first indentation in the first laminate membrane;
disposing the second laminate film over the first laminate film; and
and heat welding a portion of the first laminate membrane to a portion of the second laminate membrane. According to clause 27,
A first indentation is formed in the laminate film, and the first indentation is complementary in shape and size to the insulating layer;
a second indentation is formed in the laminate film, the second indentation being complementary in shape and size to the insulating layer; and
The steps of forming the encapsulation layer are:
disposing the thermal insulation layer in a first indentation in the laminate membrane;
folding the laminate film so that the second indentation in the laminate film is substantially aligned with the first indentation; and
and heat welding a portion of the laminate membrane to itself. According to clause 27,
A first indentation is formed in the laminate film, and the first indentation is complementary in shape and size to the insulating layer; and
The steps of forming the encapsulation layer are:
disposing the thermal insulation layer in a first indentation in the laminate membrane;
folding the laminate membrane so that a portion of the laminate membrane substantially covers the insulating layer and a separate portion of the laminate membrane; and
and heat welding a portion of the laminate membrane to itself. 34. The method of any one of claims 27-33, wherein the encapsulation layer completely surrounds the insulating layer. 35. A method according to any one of claims 27 to 34, wherein the heat welded portions of the laminate membrane are folded against one or more sides of the insulating layer.

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